New Methods for Encapsulation

The classic procedures mentioned above have their limitations, especially when it comes to encapsulating very volatile and/or reactive flavourings. In order to satisfy this demand other methods of encapsulation have been developed recently. Also, processes from the pharmaceutical industry have been adjusted to the technological and legislative requirements of the flavour industry. 

An important part of this work is the selection of the right material for encapsulating and coating. They have to be neutral in taste and they need to be approved and safe for food use. By choosing the right materials one can also achieve a better control over the release of the flavour, with the trigger being temperature, pH or the solvent used. 

On the process side, techniques like the fluid bed method, extrusion, coacervation, the submerged nozzle process and molecular inclusion have gained importance within the last 10-15 years [1-3, 7]. 

Continuous spray granulation starts off identical to spray drying, i.e. an aqueous emulsion. This granulation technology has the advantage of producing large flavoured particles of uniform size and shape without the need for any additional production steps. 

An alternative batch spray granulation process utilises the fluidised bed rotor granulator for the manufacture of spherical flavour granules. In this case a flavouring emulsion is sprayed into a fluidised bed of core material. 

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Aluminosilicate molecular sieves with the FAU structure have been crystallized in the presence of several metallophthalocyanines. A percentage of the complexes becomes included into the zeolites. The synthesis of NaX around the metal chelate represents a new method for encapsulating such complexes and modifying zeolite molecular sieves. The entrapped complexes were characterized by XRD, IR and UV-VIS spectroscopy. Preliminary results suggest the metal complexes may function as templates by modifying the gel chemistry. 

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